a-input-number 保留一位小数点

<a-input-number :min="0"
                                                        :max="100"
                                                        :step="1"
                                                        :formatter="(value)=>{
      let reg = /^(-)*(\d+)\.(\d).*$/;
      return `${value}`.replace(/\B(?=(\d{3})+(?!\d))/g, ',').replace(reg,'$1$2.$3');}"
                                                        :parser="(value)=>{
      let reg = /^(-)*(\d+)\.(\d).*$/;
      return value.replace(/\s?|(,*)/g, '').replace(reg,'$1$2.$3');
    }"
                                                        v-model="item.branch" />